Rod bending machine



W. H. COBBLE ETAL ROD BENDING MACHINE 4 Sheets-Sheet l April 3, 1962 Filed March ll, 1960 April 3, 1962 w. H. COBBLE ETAL Ron BENDING MACHINE 4 Sheets-Sheet 2 Filed March 1l, 1960 INVENTORS Mum/z #Mey /bzf Z ffm/w fr. Amen/u ATroRNl-:Y

April 3, 1962 w. H. COBBLE ETAL. 3,027,929

ROD BENDING MACHINE April 3, 1962 w. H. coBBLE ETAL 3,027,929

ROD BENDING MACHINE Filed March l1, 1960 4 Sheets-Sheet 4 INVENTORS ATTOI EY Sttes 'I'his invention relates to a rod bending machine and more particularly to a machine for simultaneously effecting a plurality of bends in a rod.

Heretofore, the formation of a plurality of bends in a straight rod has been eiiected primarily by machines capable of forming only one bend at a time. Those machines which have been constructed to form bends simultaneously in a rod are not provided with a satisfactory means for releasing the bent bar, which is usually bound in the machine between the anvils or other bending elements. In a machine which is adapted to form a plurality of bends simultaneously in a continuous operation, the problem of immediately releasing the bent bars becomes more acute, because a bent bar remaining in the machine will be straightened by the reverse operation of the bending elements returning to their original position for bending the next bar.

It is therefore an object of this invention to overcome the disadvantages enumerated by providing a rod bending machine which is capable of forming a plurality of alternate uniform bends in a rod simultaneously, automatically releasing the bent bar, and automatically repeating the sequence of bending and releasing operations.

Another object of this invention is to provide a rod bending machine capable of automatically forming uniform alternate bends in a single rod simultaneously in the same plane, the resulting rod being adapted to form a truss in a bar joist or open-web joist.

Another object of this invention is to provide a rod bending machine incorporating a fixed guide member and a moveable guide member in which alternately spaced anvil support units are adapted to move longitudinally of the guide members, adjacent support members being connected by pivoted links, the ends of these links having a lost motion pivotal connection with the support units in such a manner that a slight movement of the second guide member toward the rst guide member after a rod is bent by the anvils will automatically release the bent rod from the machine.

Another object of this invention is to provide a rod bending machine having linked longitudinally traveling anvil support units mounted in laterally reciprocal guide members, incorporating a uniform interchangeable link of novel design.

A still further object of this invention is to provide a rod bending machine which shall be of simple construction, economical of manufacture and which may be operated with a minimum of labor to form a plurality of bends simultaneously in a rod in a minimum of time.

Further objects and advantages of the invention will be apparent from the following description taken in conjunction with the drawings, wherein:

FIG. l is a front elevation of the invention with a rod placed in its initial position between the anvils, preparatory to bending;

FIG. 2 is an elevational view of the left end standard disclosed in FIG. 1;

FIG. 3 is a section taken along the line 3-3 of FIG. l with parts of the rear support column broken away and with the anvil support units, cables, rod loading mechanism and power means removed;

FIG. 4 is a section taken along the line 4-4 of FIG. l, with parts of the moveable guide member removed;

FIG. 5 is a section taken along the line 5--5 of FIG. 3;

FIG. 6 is a perspective view of an anvil support unit;

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FIG. 7 is an enlarged fragmentary view of the anvil support units and links in the same extended position of FIG. l;

FIG. 8 is a view similar to FIG. 7 in which the anvil support units and links have been contracted to their extreme bending positions;

FIG. 9 is a view similar to FIG. 8 disclosing the rod releasing position of the links;

FIG. 10 is a perspective view of the rod ejecting mechanism associated with an end link and anvil support unit;

FIG. 11 is a section taken along the line 11-11 of FrG. 1;

FIG. 12 is a fragmentary perspective view disclosing the mechanism for actuating the rod loading arms;

FIG. 13 is a fragmentary operational View of the loading device preparatory to loading;

FIG. `14 is a View similar to FIG. 13 disclosing an intermediate operational position of the loading device;

FIG. 15 is a fragmentary sectional elevation disclosing locking mechanism for the loading device.

Referring now to the drawings in more detail, a supfort frame 20 comprises a pair of vertical end members or standards 21 and 22. Each end standard 21 and 22 comprise a pair of spaced vertical I-beams 23 and 24, each pair of which have their webs in alignment, as disclosed in FIG. 4. The frame 20 also has a vertical center standard 27, and a pair of vertical rear standards 28 and 29 having top transverse arms 30 and 31, respectively.

Horizontally supported in fixed position by the standards 21, 22, 27, and depending from the top arms 30 and 31, is a first or upper stationary guide member or beam 35. The upper guide member 35 is a horizontally disposed hollow beam having a horizontal longitudinal slot 36 extending the length of the bottom of the beam 35. Within and extending the length of the beam 35 are a pair of spaced parallel tracks 37.

A second or lower vertically movable guide member or beam 40 is also horizontal and of substantially the same structure as the beam 35, but turned upside down. The lower beam 40 has a similar horizontal slot 41 and tracks 42 which are disposed in vertical alignment and below their like parts in the beam 35. To move the guide member 40 vertically toward and away from the upper beam 35, the lower beam 40 is mounted to the outer end of a horizontal cross arm 43 of each of a pair of L-shaped members having vertical arms 44 with rollers 45 and 46 mounted on horizontal axles at the top and bottom of each arm 44, as best disclosed in FIGS. 3 and 5. The rollers 45 and 46 are adapted to travel vertically in the trackways 47 of the rear standards 28 and 29. In order to move the lower beam 40, a pneumatic or hydraulic cylinder 48 depends from each top arm 30 and 31 midway between the respective standard 28 or 29 and the upper beam 35, and the corresponding piston rod 49 is connected to the cross arm 43 between the vertical arm 44 and the lower beam 40. This particular construction of the L-shaped member 43-44 affords an even balanced movement of the beam 40 by reducing the torque effect between the lower beam 40 and the standards Z8 and 29.

The opposite ends of the lower movable member 40 are provided with tongues 53 and 54, which are adapted to be vertically guided within the slots 55 formed by the adjacent flanges of the respective I-beams 23 and 24. In order to stabilize the movement of the lower beam 40 so that each end will travel at the same rate, a pair of sheaves 57-59 are mounted at each end and within the beam, as best disclosed in FIGS. 1 and 4. Only the front sheave 58 is disclosed at the right end of the beam 44) in FIG. 1, while the front sheave 57 and the rear sheave 59 of the pair mounted on the left end of thebeam are disclosed in FIG. 4. A front cable 60 is fixed at one end 61 to the bottom 0f the end standard 22, then passes over the top of the front sheave 58 and longitudinally through the hollow beam 40 and around the bottom of the front sheave 57 and is fixed at its other end 62 to the top of the end standard 21. A second or rear cable 63 is attached at one end 64 to the bottom of the end standard 21 and passes up over the rear sheave 59, extends through the hollow beam 40 crossing behind the front cable 60 and around the rear sheave, not shown, behind. front 'sheave 58, and extending upward where its other end 65 is fixed to the end standard 22. This sheave and cable arrangement permits the lower beam 40 to remain paralled to the upper beam 35 at all times and prevents either tongue 53 or 54 from sliding or binding in its respective slot 55.

Adapted to travel longitudinally in the upper stationary beam 35 are a plurality of spaced anvil support units 70, as best disclosed in FIG. l. The upper anvil support unit 71, disclosed in FIG. l, is stationarily fixed to the upper guide member 35. However, the other upper anvil support units 70 are adapted to travel freely along the bottom of the member 35. Anvil support units 72, of like structure but disposed upside down from anvil support units 70, are mounted to travel longitudinally in the top of the lower movable beam 40. FIG. 6 best discloses the detailed structure of a support unit 72, which cornprises a main body plate 73 having rollers 74 at each corner of the bottom thereof, and an anvil 75 supported above the body plate 73 by means of a supporting arm 76. The anvil support arm 76 has a spaced parallel ange 77 mounted thereon to provide a link receiving slot 78. Extending transversely through the support arm 76 and the flange 77 is a pivot pin '79. Rollers 80 mounted on vertical axes in the body plate 73 may also be provided at each end thereof for guiding the support units 72 longitudinally through the lower beam 40 by means of contacting the longitudinal slot 41, as best disclosed in FIG. ll.

Pivotally connecting adjacent upper anvil support units 70 and 71, and lower support units 72, are a plurality of uniform links 83, each comprising an elongated flat metal bar having an elongated slot 84 adjacent each end forming acuate opposite interior angles with the longitudinal axis of the link 83. Each acute angle is approximately 55 although the angle may vary within a range of 45 to 85. Each slot 84has semi-circular end portions 85 and 86 of slightly greater radius than the radius of the pivot pin 79 in order that the pin 79 may be inserted through the slot S4 and slide longitudinally of the slot from one end portion to the other. The link 83 is in its normal operative position when each pin 79 engages the end portions 85, which are located adjacent the central longitudinal axis of the link 83 and nearer the extreme ends of the link 83 than the end portions 86, as disclosed in FIGS. 7 and 8. When the pins 79 slide into the other end portions 86, more remote from the longitudinal axis and the extreme ends of the link 83 than the end portions 85, the links-83 are rotated to a rodreleasing position, as disclosed in FIG. 9. On each end of a link 83 is formed a rounded ear portion 87 facing opposite directions and in which the slots 84 are formed. A portion of the link 83 adjacent each ear 87 is cut away at 88 to provide clearance for the anvil 75 when the links 83 are in contracted position. For an elongated slot 84 forming an angle of approximately 55 with the longitudinal axis of the link 83, the cut-out portion 88 forms an angle of approximately 21 with the straight parallel edges of the link 83.

With the anvil support units 70, 71, and 72 and links 83 properly assembled, as disclosed in FIGS. 1, 7, 8, and 9, the ears 87 of a pair of adjacent links 83 overlap within the link slot 78 of an anvil support unit so that the slots 84 register with and receive the pivot pin 79. The assembly of the links 83 and the support units 70-72 is the same throughout the length of the machine, except for the end links 831 of slightly different structure to connect with the end lower support unit 721, as disclosed in FIGS. l and 10. Associated with each end link 83l is a mechanism for ejecting the bent rod 200 automatically after the rod is bent and released. Pivoted substantially midway of the link 831 by means of a hinge 91 is an ejector plate 92, which normally extends substantially fiat against one face of the link 831. An operating rod 93 is pivoted at 94 to some portion of the anvil support unit 72l to swing about a substantially horizontal axis, and slopes toward the opposite end of the link 83. A collar 95 is fixed to the operating rod 93 and supports one end of a coiled spring 96. The other end of the spring 96 abuts the base of an arm 97 extending transversely and slidable longitudinally of the rod 93. The other end of the arm 97 is attached to the plate 92 and adapted to hold the plate 92 against the face of the link 831 when the link 831 is substantially horizontal and the spring 96 is under no compression. However, when the link 831 is pivoted toward a vertical position, the spring 96 is compressed between the collar 95 and the varm 97, and by virtue of the angular relation of the operating rod 93 to the link 831, the plate 92 is biased outwardly from the face of the link 831, about the hinge 91.

Referring now the drawing in FIGS. l, l1, 12, 13, and l5, a plurality of spaced rod carriers 100 having upper forked racks 101 and lower racks 102 are mounted on the front face of the lower beam 40 toreciprocate therewith and simultaneously carry a supply of rods 200, readily accessible to the operator of the machine. Behind the rod carriers 100 is a rotatable shaft 103 mounted in bearings 104 fixed to the top of the lower member 40. Fixed in spaced relation along and rotatable with the shaft 103 are a plurality of loading arms 105. These loading arms 105 are adapted to initially assume a position in substantial alignment with or even below the upper racks 101, and subsequently to swing upwardly to apin 109 to a second crank arm 110. The crank armV 110 is fixed to the front end of a rotatable shaft 111 extending through the lower beam 40. The rear end of the shaft 111 is fixed to another crank arm 112 having a cam follower 113 at the free end thereof. Pivoted to the vertical center standard 27 by means of a pin 114 is a trip arm 115 extending above and in the vertical path of the cam follower 113. The trip arm 115 is biased downward by means of a coil spring 116 also attached Vto the vertical standard 27. Thus, when the lower guide member 40 begins t'o rise with the loading arm 105 in the position disclosed in FIG. 13, the cam follower 113 will engage the trip arm 115, which is biased downwardly by a sufficiently strong spring 116 to hold the cam follower 113 while the shaft 111 rotates as it continues to move upwardly with the beam 40. The rotation of the shaft 111 and consequently the crank arm 110 thrust the connecting rod 109 upward at a faster rate than the upward lmovement of the beam 40 to rotate the crank arm 106 and shaft 103, causing the loading arms 10S to carry a rod 200 from its initial position on the rack 101, as disclosed in FIG. 14, to its loaded position between the anvils 75 and 89 with the links 83 in their initial extended position disclosed in FIGS. 1, 7, and 11. When the lower beam 40 begins to descend, the loading arms 105 will return to their original positions in FIG. 13 because the cam follower 113 will become disengaged from the trip arm 115 and the weight of the connecting rod 108 and the crank arms 106 and 110 will reverse the rotation of the shafts 111 and 103.

`'In order to lock the loading arms 105 and shaft 103 against rotation in their initial position disclosed in FIG. 13, a locking arm 117 extends radially from the shaft 103 to normally engage a notch 118 in the lower leg of a modified bell crank 119 p-ivoted by a pin 120 to the rod carrier 100 and having its upper leg 121 extending upward beyond the rack 101, biased to the solid-line position of FIG. l by means of a spring 122. When a rod 200 is laid on the rack 101, it will force the upper leg 121 to the dashed-line position of FIG. 15 to disengage the locking arm 117 from the notch 118 and permit the shaft 103 to be rotated.

Any suitable power means for actuating the hydraulic cylinders 48 to move the lower head 40 may be employed, such as the motor 125, mounted behind the upper beam 35, for driving the compressor 126 to feed hydraulic iiuid from a fluid reservoir, such las tank 124 located within the upper beam 35 (FIGS. 1 and 3), through the supply lines 127, reversible valves 128 and cylinder feed lines 129, disclosed in dashed lines in FIG. 1. The reversible valve 128 may be actuated to reverse the flow of fluid to the cylinders 48 `in order to change the vertical movement of the beam 40 from down to up by means of a lug, not shown, on the upper anvil support unit such as 701, such lug being adapted to engage the detent 130 on the trip bar 131 having a cam surface 132 which raises the plunger 133 to actuate the valve 128 for reversing the flow of the fluid. When the lower beam 40 reaches its lowest position, designated by the dashed line 134 in FIG. l, the operator may depress the foot lever 135 to again reverse the valve 128 land cause the beam 40 to ascend.

The operation of the invention is as follows:

A single operator, Standing facing the front of the machine, as disclosed in FIG. 1, and about midway between the standards 21 and 22, may operate the machine almost completely automatically and with a minimum of manual effort to produce bent rods at a very rapid rate. With the lower beam 40 in its lowermost position disclosed by the dashed line 134 in FIG. 1, and in FIGS. 9 and 13, and a supply of straight rods 200 on the lower racks 102, the operator transfers one of these rods to the upper racks 101, thereby unlocking the shaft 103 for rotation, as disclosed in FIG. 15. By depressing the foot lever 135, hydraulic liuid is fed to the cylinders 48 causing the piston rods 49 to rise carrying with them the support arms 43 and lower member 40. As the member 40 ascends, the anvil support units 70 and 72 move longitudinally in their respective guide members 35 and 40, outward from the fixed center anvil support unit 71, thereby expanding the links 83 toward a substantially horizontal position. With the upward movement of the lower member 40, the loading arm 105 is actuated, as previously described and disclosed in FIGS. 11, 12, 13, and 14, to transfer the rod 200 from the upper racks 101 to its initial loaded position between the anvils 75 and 89 aligned above and below the rod 200.

The reversible control valve 128 is then actuated by any convenient means to reverse the flow of fluid to feed the cylinders 48 and force the piston rods 49 downward with the movable guide member 40. The descending beam 40 contracts the links 83 and anvil support units 70 and 72 to simultaneously form alternate bends in the rod 200 at each anvil 75. When the lower beam 40 reaches its lowest extreme position, as disclosed in FIG. 8. the rod 200 is completely bent, but wedged between the respective anvils 75 and 89. While the beam 40 is descending, the spring 96 on the ejector mechanism, disclosed in FIGS. l and 10, is being gradually compressed to bias the ejector plate 92 outwardly. However, -as long as the rod 200 is being bent and wedged between the anvils, the plate 92 is maintained flat against the link 831.

Again the reversible valve 128 is actuated, by the support unit 701 engaging the detent 130 or otherwise, to

reverse the flow of the fluid in the cylinders 48y and cause the retraction of the piston rods 49 to move the lower member 40 upward. The initial upward movement of the lower member 40 from its lowermost position will force the ears 87 of each link 83 to rotate in the vertical plane of the guide members outwardly from their respective pivot pins 79 because of the camming action of the elongated slots 84 on the pins 79. During this initial upward movement of the beam 40, each pin 79` will be forced from its normal position engaging the end portion 85 of the slot 84 to engage the other end portion 86, as best disclosed in FIG. 9, This slight rotational movernent of the links 83 will cause each of the anvils 89 to move away from engagement' with its respective portion o-f the bent rod 200. Consequently, the rod becomes momentarily released, and the compressed springs 96 will force the ejector plate 92 to thrust the bent rod 200 outwardly from between the anvils 89 and 75. The operator grasps the released and ejected bent rod 200 and deposits it in any convenient location while the lower member 40 continues its upward movement, =and the sequence of operations is repeated.

In order to return the slots 84 to their original positions relative to the pivot pins 79, counterweights are suspended by cables 141 in any convenient manner, such as the pulleys 142, 143 and 144, the other end of the cables 141 being connected to the outer lower anvil support units 721. The action of the counterweights 140 to take up theslack in the expansion of the links 83 and support units 70 and 72, will become effective after the bent rod 200 has been released and removed and before the lower member 40 has reached its uppermost position.

It will be apparent to those skilled in the art that various changes may be made in the invention, without departing from the spirit and scope thereof, and therefore the invention is not limited by that which is shown in the drawings and described in the specification, but only as indicated in the appended claims.

What is claimed is:

l. A rod bending machine comprising a first longitudinally extending guide member, a second longitudinally extending guide member mounted for lateral reciprocation relative to the first guide member, first longitudinally spaced 'anvil support units mounted for longitudinal movement along said first guide member, second longitudinally spaced anvil support units mounted for longitudinal movement along said second guide member and disposed between said first support units, first work engaging anvils mounted on said support units, a link pivotally connected to each adjacent pair of first and second support units, means for laterally reciprocating one of said guide members toward and away from said other guide member, second work engaging anvils mounted on said links adjacent the ends thereof, said second anvils being spaced laterally from their corresponding adjacent first anvils to receive a rod between said rst anvils and said second anvils, and means for moving adjacent ends of each pair of adjacent links away from said corresponding first anvil between them whereby the second anvils on said links are simultaneously moved away from said first anvil to release a rod bent between said anvils.

2. The invention according to claim 1 further comprising an elongated slot near the end of each link and a pin on each anvil support unit registering with a pair of slots in overlapping ends of adjacent links, the longitudinal axes of said slots being at such an angle to each other after said guide members have been moved away from each other to a rod releasing position that lateral movement of one guide member toward the other will cause each slot to cam against said pin to move said overlapping ends away from each other.

3. A rod bending machine comprising a first longitudinally extending guide member, a second longitudinally extending guide member mounted for lateral reciprocation relative to the lirst guide member, first longitudinally spaced anvil support units mounted for longitudinal movement along said rst guide member, second longitudinally spaced anvil support units mounted for longitudinal movement along said second guide'member and disposed between said rst support units, work engaging anvils mounted on said support units with the work contact surfaces of said anvils positioned outwardly of said support units, uniform interchangeable links, each link having a longitudinal axis and an elongated slot adjacent each end thereof, said slots forming acute opposite interior angles with the longitudinal axis of each link, other work engaging anvils mounted adjacent the ends of each link with the work contact surfaces of said other anvils positioned inwardly of said support units, a pin mounted on each anvil support unit outwardly of said anvil and registering with a pair of slots in overlapping ends of adjacent links, and means for reciprocating said second guide member toward and away from said rst guide member.

4. The invention according to claim 3 in which the longitudinal axes of overlapping elongated slots will move across each other to reverse their relative angular positions during the reciprocable movement of said second guide member between its extreme lateral positions.-

5. The invention according to claim 3 inv which said acute interior angles are equal and approximately 45-48".

6. The invention according to claim 3 in which one of said anvil support units is xed to said i'lrst guide member and in which means are providedV for normally biasing the end second support units to move longitudinally away from the middle of said second guide member.

7. The invention according to claim 3 in which means are provided for automatically ejecting said bent rod from between said anvils when said links have been cammed to releasing position.

8. The invention according to claim7 in which said ejecting means comprises an ejector plate mounted to move toward and away from a link, a spring adapted to be compressed when said second member is moving away from said first member to bias said ejector plate away from said link, said spring becoming decompressed to bias said ejector plate toward said link when said second member moves toward said irst member.

9. The invention according to claim 3 in which a rod carrier means is mounted on said second guide member and in which loading means actuated by the movement of said second guide member towards said rst member are provided to transfer a straight rod from said rod carrier means to a position between said anvils when said links are fully extended.

l0. The invention according to claim 9 in which said loading means comprises a loading arm pivotally mounted on said second guide member, a lever mounted on said second guide member and linked to said loading arm, a tripping arm mounted in the path of said lever and adapted to engage and actuate said lever to pivot said loading arm to transfer a rod from said carrier to saidy position between said anvils when said second guide member moves toward said rst guide member.

1l. The invention accordingito claim 3 in which said rst guide member is fixed to vertical standards at each end thereof and said second guide, member is adapted to move vertically towards and awayfrom said rst guide member Within said standards, a pair of rst and second pulleys mounted co-axially on opposite ends of said second guide member, a rst cable xed to the bottom of one of said standards and extending around the top of `the r'st pulley adjacent to one standard andV around the bottom ofvthe iirs't pulley adjacent said other standard- References Cited in the' tile of this patent UNITED STATES PATENTS 2,710,040 Boyd June 7, 1955 2,815,062 Cook et al. Dec. 3, 1957 FOREIGN PATENTS 867,035 France June 30, 1941 

